The laws, adopted in some form by at least 22 states, generally cancel a person’s duty to retreat in the face of a serious physical threat. But the 2012 shooting of Fulton’s unarmed son, Trayvon Martin, 17, and the acquittal of George Zimmerman this year provided evidence that “stand your ground” laws can be confusing and applied inconsistently, she said.

“By being unclear in when and how it is applied, stand your ground in its current form is far to open to abuse,” Fulton said in prepared testimony for the Senate Judiciary Committee.

The Democratic-led Senate was holding the hearing even though no congressional action is expected on the state policies. Even in the states, Martin’s killing, Zimmerman’s politically charged acquittal on manslaughter charges and encouragement from the Obama administration seem unlikely to spur changes in “stand your ground” laws. Most states with such laws are conservative and lean toward policies that defend gun owners’ rights.

In the shadow of the 2014 midterm elections, Illinois Democrat Dick Durbin called two panels of witnesses to the hearing room Tuesday to air the issue. Also testifying were Rep. Louie Gohmert, a Texas Republican and a staunch supporter of stand-your-ground laws, and Lucia Holman McBath.

McBath is the mother of Jordan Russell Davis, the 17-year old killed nearly a year ago when Michael David Dunn, 46, allegedly opened fire on a Dodge Durango with four teenagers inside after complaining of their loud music and saying he saw a gun. Authorities never found a gun in the vehicle, the Florida Times-Union reported.

“That man was empowered by the ‘stand your ground’ statute,” McBath said in prepared testimony. “I am here to tell you there was no ground to stand. There was no threat. No one was trying to invade his home, his vehicle, nor threatened him or his family.” Dunn’s trial has been delayed until next year, according to the newspaper.

According to the National Conference of State Legislatures, 22 states have laws that allow that “there is no duty to retreat (from) an attacker in any place in which one is lawfully present.” The states are Alabama, Arizona, Florida, Georgia, Indiana, Kansas, Kentucky, Louisiana, Michigan, Mississippi, Montana, Nevada, New Hampshire, North Carolina, Oklahoma, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Utah and West Virginia, according to the NCSL.

At least nine of those state laws include language stating one may “stand his or her ground”: Alabama, Florida, Georgia, Kansas, Kentucky, Louisiana, Oklahoma, Pennsylvania and South Carolina, according to the NCSL.

Gun rights groups such as the National Rifle Association say “stand your ground” laws are about self-defense.

“Self-defense is not a concept, it’s a fundamental human right,” said Chris W. Cox, executive director of the NRA’s Institute for Legislative Action.